similar to: R Style Guide -- Was Post-hoc tests in MASS using glm.nb

I am struggling to generate p values for comparisons of levels (post-hoc tests) in a glm with a negative binomial distribution I am trying to compare cell counts on different days as grown on different media (e.g. types of cryogel) so I have 2 explanatory variables (Day and Cryogel), which are both factors, and an over-dispersed count variable (number of cells) as the response. I know that both

I have a dataset where I have missing times (11:00 and 16:00). I would like the outputs to include the missing time so that the final time vector looks like "realt" and has the previous time's value. Ex. If meas at time 15:30 is 0.45, then the meas for time 16:00 will also be 0.45. meas are the measurements and times are the times at which they were taken. meas<-runif(18)

Colleagues Assume that I have a vector containing some text strings, some of which contain a particular character. I could like to apply "toupper" to the text before the character. For example (in this case, "|" is the particular character): ORIGINAL: TEXT <- c("aaaa", "bbb|cc", "|ddd") AFTER APPLICATION OF toupper: TEXT <-

I use the following code to create two data.frames d1 and d2 from a list: types <- c("integer", "character", "double") nlines <- 10 d1 <- as.data.frame(lapply(types, do.call, list(nlines)), stringsAsFactor=FALSE) l2 <- lapply(types, do.call, list(nlines)) d2 <- as.data.frame(l2, stringsAsFactors=FALSE) I would expect d1 and d2 to be the

Hi, is there a way to replicate a data.frame like you can replicate the entries of a vector (with the repeat-function)? I want to do this: x <- data.frame(x, x) (where x is a data.frame). but n times. And it should be as cpu / memory efficient as possible, since n is pretty big in my case. thanks for any suggestions!

Dear all, I have one problem and did not find any solution.(I have also attached the problem in text file because sometimes column spacing is not good in mail) I have a file(file.txt) attached with this mail.I am reading it using this code to make a data frame (file)- file=read.table("file.txt",fill=T,colClasses = "character",header=T) file looks like this- Chr Pos

Hi, how can I print "<=" (I mean the symbol of just one character) in the main title of a plot? for example: plot(1:10, main=paste("x <=", x)) where variable x is some number generated on the fly. Thanks John

Dear R-users I need to fit a nonlinear model to a piece of data. The model to be fitted uses past values of the input and the ouput - something like y(k) ~ f(y(k-1),y(k-2),u(k),u(k-1) ....) (k is time index). As far as I know I could use earth(MARS), nnet and etc but I am not sure how to deal with the past values since most, if not all, examples I saw formula does not take in account past

Hi guys, I need your help with the boxplot. I've to create a boxplot starting from a table (.csv) in which there are the result of a test. Each column is a question and the rows are the answer of the respondents (from 0 to 5). Some answer is missing and has been filled with NA. the table has been loaded in R with the function read.csv I created the boxplot with the function boxplot and all

I tried command as.numeric(Qty) #converting column"Qty" in object "demand" to numeric. However it remains a non-numeric value. What is the best way to convert a column of data to a numeric value in R? What is the best way to convert dates into a numeric format (or some format able to be used in an x,y scatter) while still maintaining its inherent "date" property?

Hello! I've tried for a while - but can't figure it out. I have data frame x: y=c("a","b","c","d","e") z=c("m","n","o","p","r") a=c(0,0,1,0,0) b=c(2,0,0,0,0) c=c(0,0,0,4,0) x<-data.frame(y,z,a,b,c,stringsAsFactors=F) str(x) Some of the values in columns a,b, and c are >0: I need to

I have a list called "tabs" that I would like to have the same structure as my list "eqSystem." The two look like they have the same format but they are different because when I look at their attributes, class(eqSystem[[1]]) is "call" but class(tabs[[1]]) is "formula". I want to have class(tabs[[1]]) as a call too. So what does "call" mean? And how

I have a data.frame "e" and would like to extract the 23rd column, remove any NA's and then remove any values >= 30. I can do it in steps such as this but have failed to figure out how to do it in a single line .... any suggestions? first <- e[,23] second <- first[!is.na(first)] third <- second[second<=30] thanks a bunch J -- Dr. Jim Maas University of East

Hello all, I'm running a parameter grid optimization ( ksvm, kernlab package) and the optimizer seems not to converge for certain parameters and stays in a infinity loop. Would it be possible to abort the execution after x-seconds and continue with the next parameter set? Which R function do need to use to accomplish this? I had a look at, try() etc. but they didn't seem so fit my

I am trying to run an ANOVA on my soil respiration data, but I keep getting residual sum of squares and mean square of zero. As I understand it that would mean that the model terms explain all of the variation in the response variable. That should be virtually impossible, should it not? Where do I begin troubleshooting such a problem? -- View this message in context:

Hi Dear All, Can someone give me a suggestion about which robust statistics are most appropriate for outlier detection in linear models, and is available with R ? Thanks for any idea. -- View this message in context: http://r.789695.n4.nabble.com/Robust-Statistics-for-Outlier-Detection-tp3438493p3438493.html Sent from the R help mailing list archive at Nabble.com.

Hello, I would like to create lagged and delta variables from a set of variables and then add them to a dataframe Suppose that GDPPcSa is a variable. I would like to be able to do this QuarterlyData$D1GdpPcSa = diff(GDPPcSa , 1) in an automated fashion so that I loop over Quartely data to compute the first difference of its variables and add them to the dataframe. .It would be great to get a

Hi useR's, Has anyone used the "Lars" package in R before? If so, is there any tutorial (not manual) or worked out example online for this R package that one can go through to figure out how one can use this package with lasso regression? I appreciate any help I can get in this direction. Sincerely, Vishal -- *Vishal Thapar, Ph.D.* *Scientific informatics Analyst Cold Spring

If I have 2 n-dimensional arrays, how do I compose them into a n+1-dimension array? Is there a standard R function that's something like the following, but that gives clean errors, handles all the edge cases, etc. abind <- function(a,b) structure( c(a,b), dim = c(dim(a), 2) ) m1 <- array(1:6,c(2,3)) m2 <- m1 + 10 abind(m1,m2) ==> , , 1 [,1] [,2] [,3] [1,] 1 3 5

Please, can you help me with the following? I want to include a Greek letter as part of a factor label that I need to use as factor on a xyplot. Probably this was already solved so can I get the place where I can look for? Thanks, Hugo [[alternative HTML version deleted]]